Wood chip granulometry
SUPER-PAIN chippers are the only ones to guarantee a consistent chip, with no tailing and no sawdust — directly usable with no screening required.
Granulometry determines the valorisation options
Granulometry determines whether the chips can be valorised at all. A chip that is too thick will not ferment evenly; too fine, and it reduces to sawdust, which brings its own drawbacks. The design of SUPER-PAIN chippers has been thought through from the outset to produce an optimal granulometry — exactly as Jean Pain defined it.
"It is preferable to obtain a long thin fragment rather than a short thick one."
This is not simply an opinion: it took Jean Pain several years of experimentation to reach this conclusion, starting from manual chipping with a billhook and a fork, through to the current disc chipper. We can now refine this definition further by adding that the wood fibre must be cut relatively short to allow better exchange (water penetration, bacteria and fungi in the context of fermentation or use as an absorbent material; water evacuation when seeking to dry the wood).
From the billhook to the bladed disc chipper
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1960s
The billhook and the fork
Jean Pain built his first brushwood compost heaps by hand, using brushwood of 8 mm diameter maximum. The technique worked perfectly but could not be scaled up due to the sheer physical labour involved.
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1973
First attempt: the hammer mill
Jean Pain and his nephew Étienne Bonvallet tried a hammer mill (shredder) to mechanise production. The result was disappointing: the chips were too inconsistent to easily produce compost. Screening or re-chipping was needed to achieve a satisfactory result. The hammer mill also proved prone to jamming with high-fibre plants.
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1981 — today
The solution: the sharp-bladed disc chipper
The disc chipper with fixed blades proved to be the ideal solution. Combined with a specific cutting table, it produces consistent chips with no sawdust or tailing, directly usable with no screening — regardless of wood diameter or moisture content. This system opens the door to many different valorisation applications.
Super-Pain chip size distribution
The following table shows the typical granulometric distribution of chips produced by Super-Pain chippers, measured directly at the machine outlet, with no screening. These values may vary slightly depending on wood moisture content.
Source: measurements taken on Super-Pain chips, all species combined. Granulometry obtained directly at machine outlet, no screening. The high proportion — 86.9% above 2.5 mm — is the guarantee of chips that can be valorised immediately.
View full data table
| No. | Sieve (mm) | Proportion (%) | Group |
|---|---|---|---|
| 1 | ≥ 4.0 mm | 71.2% | 86.9% > 2.5 mm |
| 2 | 3.2 mm | 8.0% | |
| 3 | 2.5 mm | 7.7% | |
| 4 | 2.0 mm | 4.8% | 7.5% between 1.6 and 2 mm |
| 5 | 1.6 mm | 2.7% | |
| 6 | 1.0 mm | 2.7% | 5.5% < 1.6 mm |
| 7 | 0.5 mm | 1.7% | |
| 8 | < 0.5 mm | 1.1% |
Why this granulometry is ideal
With 86.9% of chips above 2.5 mm and less than 5.5% below 1.6 mm, Super-Pain chips meet the requirements of every wood chip valorisation pathway.
Jean Pain compost
The 2–4 mm thickness allows optimal aerobic fermentation without asphyxiation. Sawdust would block the heap's respiration — our SUPER-PAIN chippers produce none.
Suitable for all green wood speciesRCW and mulching
Chips decompose progressively in contact with the soil, feeding mycorrhizal fungi without forming an impermeable crust.
Immediate soil applicationWood energy
Consistent chips flow smoothly through automatic boiler feed augers, with no jamming or gearbox strain. The absence of sawdust is a safety asset.
P45 chip standard compliantThermal insulation
Consistent chips with no sawdust or large splinters, usable as natural insulation (lime-washed or cement-mixed techniques) or lightweight insulating screeds.
Sustainable constructionAnimal bedding
No sawdust, no splinters — Super-Pain chips are ideal bedding for horses, cattle, sheep and small animals, with no injury risk and no respiratory irritation. Wood's natural antifungal properties keep the bedding hygienic, while chip shape promotes moisture absorption.
No sawdust or splintersEquestrian surfaces
Consistent granulometry, absorbency and low dust make our chips an ideal riding surface material: flexible, stable, virtually dust-free in summer and water-absorbent in winter. The absence of large splinters and sawdust ensures the safety and comfort of horses.
No dust, no mudWant chips like these?
Discover our Super-Pain range or ask us your questions.